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Resistive random-access memories are ideal candidates for next-generation non-volatile memories due to their simple structure, fast response, and low power consumption. One-dimensional nanostructured memories are of particular importance owing to their electron transport confinement in individual components (such as nanorods/nanowires) that can provide extra control to finely tune the electrical performance for stable and reliable memory operations. In this work, vertically oriented one-dimensional TiO 2 nanorods were fabricated via a simple and facile solvothermal technique. Besides, SnO 2 nanoparticles were embedded on TiO 2 nanorods matrix (to form a nanocomposite) and their resistive switching characteristics were evaluated and compared. Although, both devices expressed good resistive switching behavior. However, the nanocomposite device showed superior switching performance than the control (TiO 2 nanorods) one. Moreover, the nanocomposite device demonstrated additional features of multilevel data storage and the prediction of switching probabilities at lower potentials to be applied in neuromorphic computing. The governing resistive switching mechanism was explored, and the role of oxygen vacancies was identified as critical for the switching and charge transport mechanism in the investigated devices. [ABSTRACT FROM AUTHOR]

The future commercial advancement of lead-halide perovskites (LHPs) faces obstacles due to the existence of harmful lead and the inadequate stability associated with these materials. To tackle this challenge, we have prepared a Cs 3 Sb 2 I 9 perovskite single-crystalline thin film (Cs 3 Sb 2 I 9 device) using a technique based on the restricted evaporation of solvents in space, aiming for effective photodetection. The photodetector in the current study shows a responsivity (R) of around 111 mA/W and a detectivity (D∗) of approximately 3.7 × 1012 Jones. While these performance metrics are comparable to other photodetectors, there is a need for additional optimization to match the capabilities of commercial silicon and germanium-based counterparts. The examination of ultrafast transient absorption provides insights into the essential photophysics inherent in Cs 3 Sb 2 I 9. The synergy between the deformation potential and the Fröhlich effect plays a crucial role in shaping electronic dynamics. This synergy leads to the self-trapping of charge carriers, resulting in the creation of localized polarons within the Cs 3 Sb 2 I 9 lattice within just some picoseconds. The restriction of carrier mobility within Cs 3 Sb 2 I 9 arises from the self-capturing and confinement of small polarons (SPs). Furthermore, it was noted that SPs in a localized state could undergo absorption into an elevated state (photon energy ⁓ 1.60 eV). This process effectively facilitates the charge carriers' mobilization to a more dispersed eigenstate. Our research provides essential comprehension into the light-induced processes of lead-free halide perovskites (LFHPs), offering valuable insights for their prospective use in optoelectronics as promising future semiconducting agents. • Cs 3 Sb 2 I 9 perovskite single-crystalline thin film was prepared using a technique based on the restricted evaporation of solvents in space, aiming for effective photodetection. • The synergy between the deformation potential and the Fröhlich effect plays a crucial role in shaping electronic dynamics. • This synergy leads to the self-trapping of charge carriers, resulting in the creation of localized polarons within the Cs 3 Sb 2 I 9 lattice within just some picoseconds. • The restriction of carrier mobility within Cs 3 Sb 2 I 9 arises from the self-capturing and confinement of small polarons. • This process effectively facilitates the charge carriers' mobilization to a more dispersed eigenstate. [ABSTRACT FROM AUTHOR]

Extensive research efforts are currently focused on lead-free all-inorganic perovskite single crystals (SCs) due to their lower biological toxicity and improved material stability. These advancements address two significant obstacles in the implementation of practical device applications. Positive photoconductivity (PPC) under light illumination has been observed in lead-halide perovskite SCs. Given the optical activity of lead-free perovskites, it is anticipated that they will exhibit comparable characteristics. Nevertheless, we present in this study the discovery of negative photoconductivity (NPC) induced by light, coupled with a slow recovery method, in lead-free Cs 3 Bi 2 I 9 perovskite material, which was successfully synthesized through the novel top-seed solution (TSS) process. In-depth investigations using femtosecond transient reflectance (fs-TR) spectroscopy demonstrate that these unique electronic transport characteristics originate from the generation of light-triggered trap states that are metastable within the perovskite crystal lattice. We computed the performance metrics of Cs 3 Bi 2 I 9 SC detectors, encompassing detectivity (1.68 × 1012 Jones), responsivity (32 mA/W), and the current ratio (∼10257). The distinctiveness of these findings lies in the unique behavior of Cs 3 Bi 2 I 9 SCs, which, despite being optically active, exhibit retroactive photocurrent upon irradiation. This behavior has rarely been observed in other lead-free perovskite materials. • Negative Photoconductivity (NPC): The research findings revealed that Cs 3 Bi 2 I 9 SCs exhibited negative photoconductivity, suggesting that their electrical properties degrade when exposed to light. This is a significant observation as it highlights the material's susceptibility to light-induced changes. • Metastable Trap States: The study proposed that exposure to light triggers the formation of metastable trap states within the Cs 3 Bi 2 I 9 SCs. These trap states are hypothesized to play a key role in both the negative photoconductivity and the subsequent self-recovery of photocurrent in the absence of light. • Insights into Carrier Trapping and De-trapping: Investigating the resistive switching behavior in perovskite SCs provided valuable insights into the mechanisms of carrier trapping and de-trapping under different light conditions. [ABSTRACT FROM AUTHOR]

Glass samples were synthesized according to 10Li2O + 20CuO + xBi2O3 + (70 − x)B2O3, where x = 0, 10, 20, 30, 40 mol% by the melt-quenching method. The ability of the prepared glass to protect against gamma rays and neutrons was examined experimentally and theoretically. The mass attenuation coefficient (MAC) was calculated experimentally at energies of 0.662, 1.173, and 1.333 MeV using 137Cs and 60Co sources. The obtained results were compared with the theoretical ones using a Phy-x/PSD software program version 0.1.0.0. It was found that the experimental and theoretical results are very agreed upon. Moreover, other nuclear radiation shielding parameters were evaluated. The results showed that the addition of bismuth oxide leads to an improvement in the ability of the composite glass to attenuate gamma rays by increasing the values of MAC and Zeff, while it led to a decrease in the HVL and MFP, as well as the EBF and EABF. The results also showed that the addition of copper oxide led to an improvement in the ability of the present glass to slow down fast neutrons. Sample BiS40 showed the best result for gamma ray attenuation and sample BiS10 gave the best result for fast neutron removal cross section. The results were compared with some materials used for gamma ray shielding and fast neutron removal cross section, and it was concluded that samples Bi40 and BiS10 outperformed all commercial materials. [ABSTRACT FROM AUTHOR]

The aim of this paper is to the synthesis of ZnO– Bi 2 O 3 nanocomposites and characterization their optical, structure, and radiation shielding properties. The microwave –assisted hydrothermal method was adopted for the synthesis of ZnO– Bi 2 O 3 nanocomposites coded as 100Z, 25B075Z, and 50B-50Z. The FTIR and UV spectra of the samples were analysed to obtain their optical and chemical structure features. Also, the gamma-ray photon shielding parameters of the nanocomposites were evaluated using the EPICS2017 data library and by Geant4 Monte Carlo simulations for photon energies 1 keV–10 MeV. The FTIR spectrum analysis confirms the chemical bond structure of the samples. On the other hand, the optical bandgap of the nanocomposites decreased from 3.3 to 2.95 eV as the Bi 2 O 3 nanoparticles increased in the samples. Obtained values of the mass attenuation coefficients of the samples increased in the order of 100Z, 25B075Z, and 50B-50Z. Value of the effective atomic number varies from 13.91 to 29.55, 20.30–55.97, and 26.70–68.97 for 100Z, 25B-75Z, and 50B-50Z correspondingly. The 100Z, 25B075Z, and 50B-50Z nanocomposites were found to have comparable photon shielding ability with respect to high density common commercial glass shields. The present nanomaterials could be adopted as additives to enhance photon shielding competence of existing composite materials. [ABSTRACT FROM AUTHOR]

Boro-zinc-tellurite glasses in the chemical composition of xTeO2–(30 − x)Li2O–20ZnO–50B2O3 (x is ranging from 0 to 20 mol% with step of 5) were systematically studied by means of their optical features such as molar polarizability (αm), molar refraction (Rm), optical transmission (T), metallization principle (M), and reflection loss (RL). Moreover, the Monte Carlo method (via FLUKA code) was applied to investigate the photon and neutron attenuation properties by estimating the mass attenuation coefficient (MAC) of the glasses involved. The MAC values were then utilized to assess various photon attenuation parameters such as HVL, EAN, and MFP. Finally, an extended comparison was achieved between the MFP values of the present glasses and those of various commonly used radiation shields. The results showed that the general trend in MAC throughout the energy spectrum was (TL1)MAC < (TL2)MAC < (TL3)MAC < (TL4)MAC < (TL5)MAC. The TeO2 addition (the substitution of Li2O by TeO2) has a notable impact to increase the LAC values indicating to improve the photon attenuation ability of the current glass specimens. The maximum Σ R value was around 0.12 cm−1 for TL1 glass specimen. The investigated glasses could be used for various radiation applications as non-toxic and transparent shields against photon and neutron radiations. [ABSTRACT FROM AUTHOR]

Low temperature and more efficient sol-gel auto combustion process was utilized to synthesize Co 0.3 Li 0.1 Ca 0.5 Fe 2.1- x La x O 4 [ La-CLCF ] spinel ferrites (where x = 0.00, 0.01, 0.02, 0.03, 0.04, and,0.05). The La-CLCF sample's structural, optoelectrical, dielectric, and magnetic properties were examined as a result of La3+ doping. All synthesized La-CLCF samples have single-phased spinel matrix, according to X-ray diffraction (XRD) analysis. It was found that the crystallite size was 11 nm, and the bandgap energy of 3.45 eV for La3+ doping x = 0.03. The resistivity and activation energy both were increased with the substitution of La3+ in the CLCF spinel matrix, while the peak position of temperature coefficient of resistance (TCR) percentage was − 3.92%/K at 372 K for sample x = 0.03. The alternating current conductivity improves with frequency, whereas the dielectric constant and tangent loss decrease as frequency increases. Further, the saturation magnetization and the microwave operating frequency for all the samples were reduced with the doping of La3+. The minimum coercivity was 242 Oe at x = 0.03. Our study suggested that the Co 0.3 Li 0.1 Ca 0.5 Fe 2.07 La 0.03 O 4 sample is tested as an active material for potential use in high-frequency applications, electromagnetic wave absorbing material, and evaluating the sensitivity of infrared (IR) detectors used in night vision bolometers. [Display omitted] • Co 0.3 Li 0.1 Ca 0.5 Fe 2.1- x La x O 4 spinel ferrites preparation via SGAC route. • The peak position of TCR was − 3.92%/K at 372 K for sample x = 0.03. • The minimum coercivity was 242 Oe for La3+ doping x = 0.03 • The sample x = 0.03 is a potential candidate for high-frequency applications, electromagnetic wave absorbing material, and bolometers. [ABSTRACT FROM AUTHOR]

The impact of the insertion of Pb2+ ions into the Li2O–BaO–B2O3 based glass matrix has been investigated. The Archimedes' method was used to determine the density (ρ) and, as a result, the molar volume (Vm) of the samples. The ρ of the glasses increased from 2.917 to 5.003 (g/cm3), and the Vm increased from 24.155 to 27.074 (cm3/mol). The optical band gap of the samples was determined based on their UV–visible spectra. The structural study of the present glasses has been carried out by XRD patterns and FTIR spectra analysis. Numerous theoretical methods were used to calculate some parameters such as ionic radius, optical basicity, non-linear refractive index, and oxide ion polarizability. The mass attenuation coefficient MAC was obtained experimentally as well as theoretically by the Phy-X/PSD software programs and the obtained results were in very good agreement. The half-value layer HVL, mean free path (MFP), effective atomic number (Zeff), atomic cross-sections and electron cross-sections were evaluated for all the present glass samples. In addition, exposure build-up factor and energy exposure build-up factor were estimated for each glass up to penetration depths of 40 MFP. Moreover, the effective neutron removal cross-section (ƩR) was also calculated. The shielding properties of the prepared glass samples were compared with different concrete shielding materials, and commercial glasses, therefore, the prepared glasses outperformed all the aforementioned materials in terms of gamma ray shielding ability. [ABSTRACT FROM AUTHOR]

In the present study, Sr0.7Bi0.2TiO3 is mixed with [(K0.5Bi0.5)(Mg1/3Nb2/3)O3] to form a solid solution of [(1 − x)SBT–x(KB)(MNb), x = 0.02, 0.04, 0.06, 0.1]. From the XRD results, it is indicated that KB is the main substituent for SBT ceramic at the A‐site. The breakdown strength (BDS) of ceramic gradually increases with an increase in doping content and achieves a high value of 280 kV/cm for x = 0.06. In addition, the 0.94SBT–0.06(KB)(MNb) ceramic shows excellent temperature stability (−55 to 140°C), a high recoverable energy density (Wd)—2.6 J/cm3, and an efficiency (η)—88% at 280 kV/cm. Therefore, 0.94SBT–0.06(KB)(MNb) ceramic is one of the possible materials for energy storage capacitor applications. [ABSTRACT FROM AUTHOR]

This research article aims to study the effect of CdO addition on the radiation shielding characteristics of boro-tellurite glasses in the composition of 50B 2 O 3 - (50-x) TeO2- xCdO, where x = 0, 10, 20, 30, 40 and 50 mol%. These glasses were exposed to gamma radiation and the transmitted gamma photons were evaluated for energies varying from 15 keV to 15 MeV using Geant4 simulation toolkit. The number of transmitted photons was then used to characterize the gamma shielding for the studied glasses in terms of linear/mass attenuation coefficients, MFP, Z eff , and HVL. The simulation outcomes were theoretically confirmed by using Phy-X software. The beta (electron) shielding characterization of the involved glasses was also investigated by determining the projectile range and stopping power using ESTAR software. Additionally, the fast neutron shielding characterization of the glasses was achieved by evaluating removal cross-section (Σ R). The results reveal that the CdO has a small influence on the shielding performance of the boro-tellurite glasses against gamma, beta, and neutron radiations. The shielding performance of the boro-tellurite glasses was compared with that of common shielding materials in terms of MFP. It can be concluded that the boro-tellurite glasses regardless of the concentration of CdO content have promising shielding performance to be used for radiation applications. [ABSTRACT FROM AUTHOR]

In the present work, we have studied the effect of Sb2O3 addition on gamma, neutron, and charged particles attenuation properties of tellurite glasses in the chemical structure of 84TeO2 + xSb2O3 + 1V2O5 + (15-x)Nb2O5, where x is between 0 and 15 mol% with step of 5. Monte Carlo simulations (by using FLUKA code) were employed to investigate the gamma attenuation parameters for photon energies of 0.6, 1.25, 1.5, 2, 3, 5, and 10 meV. For every photon energy, the results of FLUKA simulations were theoretically approved using the XCOM approach. The obtained results show that the Sb2O3 addition increased the mass attenuation coefficient (µ/ρ) ranges from 0.03318 to 0.08003, 0.03334–0.08021, 0.03349–0.08038, and 0.03363–0.08054 cm2 g−1 for TSVN1, TSVN2, TSVN3, and TSVN4, respectively. For the studied glasses, the maximum (minimum) effective atomic number (Zeff) was obtained at 10 meV (1.25 meV) with corresponding values of 28.85 (21.58), 29.80 (22.27), 30.77 (23.00), and 31.78 (23.77). The exposure rate (ER) follows the trend: (ER)TSVN4 > (ER)TSVN3 > (ER)TSVN2 > (ER)TSVN1. Different effects of Sb2O3 addition were observed on the shielding properties for the thermal and fast neutrons. Finally, the influences of Sb2O3 addition on the attenuation features of the studied glasses were discussed in detail for charged particles such as protons, alpha particles, and electrons. It is concluded that the investigated glass specimens can be utilized for various nuclear applications as non-toxic shields against the radiation of gamma, neutron, and charged particles. [ABSTRACT FROM AUTHOR]

The gamma-ray and fast/thermal neutron shielding properties of bismo-borate glasses modified with Nd 2 O 3 in the form B 2 O 3 –Bi 2 O 3 –SrO-Nd 2 O 3 (BBSN0.0-BBSN5.7) were investigated. The newly developed Phy-X/PSD software and Geant4 simulation code were performed to achieve this goal by evaluating several parameters such as MAC, gamma photons dose rate, FNRCS, and scattering/absorption lengths and cross sections for thermal neutrons. At low photon energy; 0.015 MeV, MAC values varied from 76.72, 76.57, 76.43, 76.29, 76.10, and 75.93 cm2 g−1 for BBSN0.0, BBSN1.0, BBSN2.0, BBSN3.0, BBSN4.3, and BBSN5.7, respectively. The HVL followed reversible trend as follows; BBSN0.0 > BBSN1.0 > BBSN2.0 > BBSN3.0 > BBSN4.3 > BBSN5.7. The highest values for Z eff were found at low energy photon range (0.015 MeV) with the values of 76.71, 76.35, 76.00, 75.65, 75.21, and 74.75, while the lowest values were found at 1.5 MeV; 21.32, 21.42, 21.52, 21.61, 21.73, and 21.87 for BBSN0.0 – BBSN5.7, respectively. The gamma dose rate has a dramatic decrease with increasing the glass thickness from 1 mm to 5 mm. Furthermore, glasses with the highest concentration of Nd 2 O 3 show the best thermal/fast neutron shielding capability among the investigated glasses. One can conclude that BBSN5.7 glass owns the best shielding capacity among all BBSN glasses due to the highest LAC values comparing to other selected ones. [ABSTRACT FROM AUTHOR]

In this paper, the hydrogen storage properties of the MmNi 4.6 Al 0.4 and MmNi 4.6 Fe 0.4 compounds are compared experimentally and theoretically. The experimental curves of the activation process, experimental isotherms of absorption and the Van't Hoff's plot were first investigated. Following that, a theoretical model is contrasted with the experimental data. The mathematical equations of this model contain parameters, such as the number of hydrogen atoms per site (n 1 , n 2), the densities of the receiving sites (N 1m , N 2m), and the energy parameters (P 1 , P 2). All these parameters are obtained by numerically adjusting the experimental data. Depending on the applied temperature, the relevant parameters of the suggested model were identified and described. Entropy, internal energy, and other thermodynamic variables that govern the absorption reaction were all calculated and displayed as a function of pressure and temperature. • Measurement of hydrogen absorption isotherms by MmNi 4.5 Al 0.4 and MmNi 4.6 Fe 0.4 compounds. • Validation of experimental data by a mathematical model using statistical physics. • Determination of the steric parameters governing the absorption reaction. • Calculation of the thermodynamic functions of the absorption reaction. [ABSTRACT FROM AUTHOR]

Combined effects of using inclined partition and magnetic field on the cooling performance of double slot jet impingement are analyzed with finite element method. Two different shear thinning nanofluids are used while experimental data is available for the rheological properties. Different values of of Reynolds number (Re between 100 and 1000), velocity ratio (VR, between 0.2 and 1), opening ratio (OR, between 0.05 and 0.95), magnetic field strength (Ha, between 0 and 30) and inclination of partition (Ω , between 0 and 40) are used. It is observed that varying VR of the jets, size/inclination of the partition, magnetic field strength and nanfluid type, can be used to control the local and average convective heat transfer and cooling performance features effectively. The average Nusselt number (Nu) rises with higher VR while at the highest VR the amount of increments are 23.5 % and 28.5 % with first (NF1) and second (NF2) nanofluid (NF). When magnetic field is imposed, effects of OR becomes important with NF1 at the lowest strength of magnetic field. Average Nu reduces with higher magnetic field strength for NF1 while 14.4 % reduction for the highest strength at OR = 0.95 is achieved. However, for NF2 the trend is opposite and 18.8 % increment is obtained. Variations in the average Nu becomes 7.6 % and 1.8 % for NF1 and NF2 when inclination of the partition is changed. The cooling performance is estimated by using a feed-forward network modeling approach in terms of average Nu for NF1 and NF2 by using 25 neuron in the hidden layer. [ABSTRACT FROM AUTHOR]

In this work, efficient synthesis of isoindolin‐1‐one‐3‐phosphonates under catalyst‐ and solvent‐free conditions was reported to afford the desired compounds in excellent yields with potent pharmacological properties. The synthesis method involves the preparation of isoindolin‐1‐one‐3‐phosphonates by a "one‐pot" three‐component reaction of 2‐formylbenzoic acid with primary amines and dimethyl phosphite under solvent‐ and catalyst‐free conditions. All new compounds were characterized by 1H NMR, 13C NMR, FT‐IR and elemental analysis techniques. The compounds were investigated for their bioactivities against a group of microorganisms, Leishmania major, Toxoplasma gondii parasites, and the DA‐MB‐231 and MCF‐7 cancer cell lines in vitro. Compound 4a was found to be the most active against L. M. luteus, L. monocytogenes and C. albicans microorganisms, with inhibition zones of 35, 22 and 38 mm, respectively. The compounds were also investigated for their antiparasitic activities, and compounds 4a and 4b were the most active against L. major amastigotes and promastigotes with EC50 < 1 μM. All tested compounds had potent anticancer activity against the MDA‐MB‐231 and MCF‐7 human cell lines with EC50 < 1.5 μM. Compounds 4a and 4b are good drug candidates for antimicrobial, antileishmanial and anticancer drug discovery, and further in vivo studies are highly recommended prior to any clinical trials. [ABSTRACT FROM AUTHOR]

Pyrazole derivatives correspond to a family of heterocycle molecules with important pharmacological and physiological applications. At present, we perform a density functional theory (DFT) calculations and a quantitative structure–activity relationship (QSAR) evaluation on a series of 1‐(4,5‐dihydro‐1H‐pyrazol‐1‐yl) ethan‐1‐one and 4,5‐dihydro‐1H‐pyrazole‐1‐carbothioamide derivatives as an epidermal growth factor receptor (EGFR) inhibitory activity. We thus propose a virtual screening protocol based on a machine‐learning study. This theoretical model relates the studied compounds' biological activity to their calculated physicochemical descriptors. Moreover, the linear regression function is used to validate the model via the evaluation of Q2ext and Q2cv parameters for external and internal validations, respectively. Our QSAR model shows a good correlation between observed activities IC50 and predicted ones. Our model allows us to mitigate time‐consuming problems and waste chemical and biological products in the preclinical phases. [ABSTRACT FROM AUTHOR]

In this study, a series of unsymmetrical 1,3-disubstituted benzimidazolium chlorides 2a–g with two nitrogen atoms substituted by different alkyl groups were synthesized in high yields as N-heterocyclic carbene (NHC) precursors. These benzimidazolium salts were then converted into the corresponding Pd–NHC complexes of the PEPPSI family (PEPPSI = pyridine-enhanced precatalyst preparation, stabilization, and initiation) 3a–g. The structures of all compounds were characterized by 1H nuclear magnetic resonance (NMR) spectroscopy, 13C NMR spectroscopy, infrared spectroscopy, and elemental analysis, which support the proposed structures. The structure of the 3c complex was determined by X-ray crystallography. More detailed structural characterization of the 3c complex was performed through single-crystal X-ray diffraction, which supports the proposed structures. The Pd–NHC–PEPPSI complexes were used as catalysts in the direct C5-arylation of 2-acetyl furan, 2-acetylthiophene, and 2n-propylthiazole with different aryl bromides. These complexes exhibited moderate-to-high catalytic activities and selectively at the C5 position. Furthermore, the Pd–NHC–PEPPSI complexes were evaluated for their potential antibacterial properties against a panel of bacterial strains, such as Micrococcus luteus, Listeria monocytogenes, Salmonella typhimurium, Staphylococcus aureus, Candida albicans, and Pseudomonas aeruginosa. The Pd–NHC–PEPPSI complex 3f showed better activity than ampicillin against Micrococcus luteus, with an MIC of 0.035 mg mL−1. In addition, the antioxidant activities of the complexes 3d and 3f showed considerable free radical scavenging activity. [ABSTRACT FROM AUTHOR]

The cooling performance of jet impinging hybrid nanofluid on a rotating hot circular cylinder was numerically assessed under the effects of multiple magnetic fields via finite element method. The numerical study was conducted for different values of Reynolds number ( 100 ≤ Re ≤ 300 ), rotational Reynolds number ( 0 ≤ Rew ≤ 800 ), lower and upper domain magnetic field strength ( 0 ≤ Ha ≤ 20 ), size of the rotating cylinder (2 w ≤ r ≤ 6 w) and distance between the jets (6 w ≤ H ≤ 16 w). In the presence of rotation at the highest speed, the Nu value was increased by about 5% when Re was increased from Re = 100 to Re = 300. This value was 48.5% for the configuration with the motionless cylinder. However, the rotations of the cylinder resulted in significant heat transfer enhancements in the absence or presence of magnetic field effects in the upper domain. At Ha1 = 0, the average Nu rose by about 175%, and the value was 249% at Ha1 = 20 when cases with the cylinder rotating at the highest speed were compared to the motionless cylinder case. When magnetic field strengths of the upper and lower domains are reduced, the average Nu decreases. The size of the cylinder is influential on the flow dynamics and heat transfer when the cylinder is rotating. An optimum value of the distance between the jets was obtained at H = 14 w, where the Nu value was highest for the rotating cylinder case. A modal analysis of the heat transfer dynamics was performed with the POD technique. As diverse applications of energy system technologies with impinging jets are available, considering the rotations of the cooled surface under the combined effects of using magnetic field and nanoparticle loading in heat transfer fluid is a novel contribution. The outcomes of the present work will be helpful in the initial design and optimization studies in applications from electronic cooling to convective drying, solar power and many other systems. [ABSTRACT FROM AUTHOR]

We performed a structural study followed by theoretical analysis of the chemical descriptors and biological activity of a series of 5-thiophen-2-yl pyrazole derivatives as potent and selective cannabinoid-1 (CB1) receptor antagonists. The structures and molecular properties of these compounds were obtained using a DFT-D3 (B3LYP(+D3)) approach in conjunction with the 6-311G(d,p) basis set. We also derived the physicochemical properties and the binding of these derivatives interacting with the CB1 receptor. Computations show that all of them present the same molecular subunit structure, miming that of rimonabant, an efficient CB1 antagonist. The 3D structure of this subunit, important for the interaction with the receptor, is strongly influenced by long-range interactions. Moreover, we derived a QSAR equation to model the biological activity of this series. Close agreement with experimental data is found. Moreover, molecular docking studies were carried out between the most active compound and both the inactive and active states of the CB1 receptor. Results reveal high affinity between this compound and the inactive CB1 conformation, mainly governed by van der Waals forces. In conclusion, our work suggests that this compound could be a novel efficient inhibitor of CB1. [ABSTRACT FROM AUTHOR]

New rhodium(I) N-heterocyclic carbene (NHC) complexes 3a–f were synthesized in good yields by the reactions of rhodium dimer [Rh(OMe)(cycloocta-1,5-diene:COD)]2 with benzimidazolium salts 2a–f in tetrahydrofuran. All the complexes were characterized by IR, 1H-NMR, and 13C-NMR spectroscopy, DART-TOF mass spectrometry (for 3b, 3d and 3f) and elemental analysis. All complexes were used as catalysts in the hydrosilylation of acetophenone derivatives with triethylsilane at 80 °C for 1 h. These Rh(I) NHC showed good catalytic performance for the hydrosilylation of acetophenone derivatives by using 1 mol % of the rhodium complexes. In addition the new rhodium(I) NHC complexes were tested against MCF7 and MDA-MB-231 cancer cells, Micrococcus luteus LB 14110, Listeria monocytogenes ATCC 19117, Salmonella Typhimurium ATCC 14028, Staphylococcus aureus ATCC 6538, Pseudomonas aeruginosa and Candida albicans microorganisms. The synthesized rhodium(I) NHC complex 3f was found the most active against MCF7 cancer cells (half-growth inhibition concentration (IC50) = 0.3 µg mL−1), as well as the most potent antimicrobial against L. monocytogenes ATCC 19117 (inhibition zone (IZ) = 29 mm). Moreover, the antioxidant activity determination of these complexes was studied with the DPPH (2,2-diphenyl-1-picryl-hydrazyl-hydrate) and compared with gallic acid and butylated hydroxytoluene. [ABSTRACT FROM AUTHOR]

In present research, we employed sol-gel auto-combustion method to synthesize soft ferrites, specifically Ca 0.5 Co 0.5 Cr x Fe 2-x O 4 , with Cr3+ doping, where x = 0.0, 0.1, 0.2, 0.3, 0.4, 0.5. As the Cr3+ concentration increased, we observed decrease in both the average crystallite size (from 16.4 nm to 13.5 nm) and lattice constant (form 8.3 Å to 8.2 Å). Notably, the Ca 0.5 Co 0.5 Cr 0.3 Fe 1.7 O 4 sample exhibited the highest AC conductivity at room temperature. Raman spectroscopy confirmed the presence of five active molecular vibrational modes, namely A 1g , E g, and 3T 2g. Direct current (DC) resistivity decreased with the increasing concentration of Cr3+, and the Ca 0.5 Co 0.5 Fe 2 O 4 sample displayed the maximum DC resistivity (6.81 × 108 ohm cm) at a Curie temperature of 383 K. Magnetic properties of soft ferrites, characterized through M-H loop analysis, revealed coercivity values in the range of H C = 1242.6 Oe to 660.8 Oe. These synthesized ferrites exhibit potential applications in longitudinal recording media owing to their performance in the microwave frequency range (6.0 GHz to 13 GHz), consistent DC resistivity, and stable dielectric constant. [Display omitted] • Ca 0.5 Co 0.5 Cr x Fe 2-x O 4 (0.0 ≤ x ≤ 0.5) ferrites were prepared by sol-gel auto combustion. • Dielectric factors exponentially decreased as a function of frequency. • The maximum ac conductivity was revealed by sample x = 0.3 at room temperature. • Maximum DC resistivity (6.8 × 108 Ω-cm) was shown by sample Ca 0.5 Co 0.5 Fe 2 O 4. • Microwave frequency range confirmed the ferrites are best for microwave devices. [ABSTRACT FROM AUTHOR]

(1−x)[0.94Bi0.5Na0.5TiO3 – 0.06BaTiO3]−xLa0.33NbO3 (x = 0, 0.02, 0.04, 0.06, 0.08, 0.10) (BNBT-LN) bulk lead-free relaxor ferroelectric ceramics were synthesized via solid-state sintering method. Phase, microstructure and energy storage properties were determined. The X-ray diffraction (XRD) revealed a single perovskite phase for compositions of x ≤ 0.02, while the second phase of Bi2Ti2O7 along with the parent phase for x ≥ 0.04. Dense microstructure with a decrease in grain size has been achieved via LN doping. The addition of LN decreased the remnant polarization (Pr), and coercive field (Ec), while increased the difference between the maximum polarization (Pmax) and remnant polarization (Pr). The high energy-storage density of 2.96 J/cm 3 and high recoverable energy density of 1.66 J/cm3 at a breakdown electric field of 214 kV/cm were achieved for the composition of x = 0.02 with good temperature stability satisfying the condition of Δεr /ε r200 °C ≤ ± 15% in a working temperature range of 70 °C to 400 °C. Similarly, a less discharge time of < 4 µs achieved in this study for x = 0.02. These results demonstrate that this material may be a good candidate material for power pulsed applications. [ABSTRACT FROM AUTHOR]

We study simple mathematical models for the dynamics of interactive wild and sterile insect populations. As well as being mathematically tractable, these models can be used as first approximations to real situations occurring with the Sterile Insect Technique (SIT) in which sterile males are released to reduce or eradicate a pest population. This is a method of biological control which can effectively help contain the spread of many pest insects such as the Red Palm Weevil (RPW). Models formulated in this paper are continuous-time, include a strong Allee effect that captures extinction events, and incorporate different strategies of releasing sterile insects. We perform basic studies of dynamical features of these models, with an emphasis on the condition of excitation, and the impact of the different release methods is investigated. Our findings are also demonstrated with some numerical examples. [ABSTRACT FROM AUTHOR]

New benzimidazolium salts were synthesized as N-heterocyclic carbene precursors. These NHC precursors were metallated with Cu2O and CuI in acetone and water under reflux to give novel copper(I) complexes. The structures of these benzimidazolium salts and copper(I) complexes were characterized on the basis of elemental analysis, 1H NMR, 13C NMR, IR and LC–MS spectroscopic techniques. The (NHC)Cu(I) complexes 3–4 were tested against MCF7 and MDA-MB-231 cancer cells, Escherichia coli, methicillin-resistant Staphylococcus aureus (MRSA) and Candida albicans microorganisms, Leishmania major promastigotes and amastigotes, Toxoplasma gondii parasites and against Vero cell line in vitro. The synthesized copper NHC carbene complex 4b (1,3-bis(2,3,4,5,6-pentamdthylbenzyl)-2,3-dihydro-1H-benzo[d]imidazol-2-yl)copper(I) chloride) was the most active against MCF7 cancer cells (half growth Inhibition Concentrations (IC50) = 0.3 µg mL−1), as well as the most potent antimicrobial against E. coli (inhibition zone (IZ) = 23.3 mm), MRSA (IZ = 25.5 mm) and C. albicans (IZ = 28.5 mm) besides its antileishmanial activities against L. major promastigotes and amastigotes (IC50 < 0.04 µg mL−1). Compound 4c (1,3-bis(4-(tert-butyl)benzyl)-2,3-dihydro-1H-benzo[d]imida-zol-2-yl)copper(II) bromide) is the most potent anticancer against MDA-MB-231 cancer cells IC50 = 0.4 µg mL−1). Compound 4e (5,6-dimethyl-1,3-bis(2,4,6-trimethylbenzyl)-2,3-dihydro-1H-benzo[d]imidazol-2-yl)copper(I) chloride) is the best suitable antitoxoplasmal drug candidate due to its SI of 16.5. These candidates need further study to identify mode of action and drug standardization. [ABSTRACT FROM AUTHOR]

The series of Zn 0.4 Co 0.6−x Mg x Fe 1.9 La 0.1 O 4 (x = 0.0, 0.15, 0.30, 0.45, 0.6) nanoferrites prepared via co-precipitation technique. Scherrer and Williamson-Hall (W-H) methods were used to find the crystallite size (29.6–39.2 nm and 31.6–36.3 nm, respectively) and lattice constant was calculated (8.406–8.395 Å). Moreover, Fourier transform infrared (FTIR) spectroscopy revealed the existence of absorption bands along with functional groups. The vibrations of O2- ions at the tetrahedral and octahedral sites were shown by the Raman five active modes. DC resistivity reduced in the range of 5.2961 × 108 Ω cm to 9.6453 × 107 Ω cm for x = 0.0 to x = 0.6, respectively. The maximum DC resistivity and activation energy (0.1035 eV) were obtained at the parent sample (Zn 0.4 Co 0.6 Fe 1.9 La 0.1 O 4). The optical bandgaps reduced from 2.61 to 1.47 eV, as the Mg2+ contents increased. With increasing frequency the dielectric loss and the dielectric constant decrease. The magnetic parameters such as saturation magnetization (M s = 60.82–25.94 emu/g), remnant magnetization (M r = 47.82–18.64 emu/g), and coercivity (H c = 1334–511 Oe) demonstrated reducing trends with the increase of Mg2+ doping. The best magnetic behavior of the as-prepared samples suitable in microwave devices was observed for Zn 0.4 Co 0.6 Fe 1.9 La 0.1 O 4 sample. [Display omitted] • Zn 0.4 Co 0.6−x Mg x Fe 1.9 La 0.1 O 4 nanoferrite powder prepared by co-precipitation route. • Crystallite size was minimum at x = 0.3. • The optical band gap energy decreased in the range of 2.61 – 1.47 eV. • DC resistivity also reduced from 5.2961 × 108 Ω cm to 9.6453 × 107 Ω cm. • Based on magnetic properties the sample Zn 0.4 Co 0.6 Fe 1.9 La 0.1 O 4 is suitable in microwave devices. [ABSTRACT FROM AUTHOR]

• A hybrid power, heating, cooling and fresh water generation system is designed. • SOFC-GT, ORC, HDH desalination are integrated with utilization of LNG cold energy. • The system has net energy efficiency of 85.65% and exergy efficiency of 63.29%. • Sensitivity analysis and detailed exergy destruction investigation is reported. • The parallel system configuration provides flexibility and variable output range. A multigeneration system is proposed to address the high temperature exhaust emissions of solid oxide fuel cells and the increasing demand for power, fresh water, cooling, and heating utilities. Thermodynamic assessment of the hybrid solid oxide fuel cell system integrating gas turbine, organic Rankine cycle (ORC) and humidification dehumidification (HDH) desalination system with liquified natural gas cold energy utilization is conducted. SOFC being the primary mover, the influence of key parameters such as cell operating temperature and pressure on overall system output performance is studied. In addition to the conventional cascade heat recovery mode, a parallel configuration of the system is also designed and analyzed for varying load demand. This design provides flexibility in operation. Under design conditions the net power generated, heating load, cooling load and fresh water produced by the system are 2390 kW, 584 kW, 58 kW and 209 kg/hr, respectively. The results show that the system net energy, exergy and electrical efficiencies are 85.65%, 63.29% and 64.51%. The major exergy destruction sources are the air preheater, afterburner and water preheater contributing to 28.3%, 16.5% and 15.8% of the total destruction. The exergy destruction of the SOFC subsystem is highest in both series and parallel designs amounting to about 888 kW. In parallel mode, the exergy destruction rate of ORC decreases from 15% to 10% while that of heating and desalination subsystem increase by 2% each. The parallel configuration is flexible in terms of output power, heating load and produced fresh water that have a range of 2303–2470 kW, 258–784 kW and 189–2493 kg/hr, respectively. [ABSTRACT FROM AUTHOR]

The forced convection of non-Newtonian nanofluid for a backward-facing flow system was analyzed under the combined use of magnetic field and double rotating cylinders by using finite element method. The power law nanofluid type was used with different solid volume fractions of alumina at 20 nm in diameter. The effects of the Re number ( 100 ≤ Re ≤ 300 ), rotational Re number ( − 2500 ≤ Rew ≤ 3000 ), Ha number ( 0 ≤ Ha ≤ 50 ), and magnetic field inclination ( 0 ≤ γ ≤ 90 ) on the convective heat transfer and flow features were numerically assessed. The non-Newtonian fluid power law index was taken between 0.8 and 1.2 while particle volume fractions up to 4% were considered. The presence of the rotating double cylinders made the flow field complicated where multiple recirculation regions were established near the step region. The impacts of the first (closer to the step) and second cylinders on the heat transfer behavior were different depending upon the direction of rotation. As the first cylinder rotated in the clockwise direction, the enhancement in the average heat transfer of 20% was achieved while it deteriorated by approximately 2% for counter-clockwise directional rotation. However, for the second cylinder, both the rotational direction resulted in heat transfer augmentation while the amounts were 14% and 18% at the highest speeds. Large vortices on the upper and lower channel walls behind the step were suppressed with magnetic field effects. The average Nu number generally increased with the higher strengths of the magnetic field and inclination. Up to 30% increment with strength was obtained while this amount was 44% with vertical orientation. Significant impacts of power law fluid index on the local and average Nu number were seen for an index of n = 1.2 as compared to the fluid with n = 0.8 and n = 1 while an average Nu number of 2.75 times was obtained for the flow system for fluid with n = 1.2 as compared to case for fluid with the n value of 0.8. Further improvements in the local and average heat transfer were achieved with using nanoparticles while at the highest particle amount, the enhancements of the average Nu number were 34%, 36% and 36.6% for the fluid with n values of 0.8, 1 and 1.2, respectively. [ABSTRACT FROM AUTHOR]